Questions tagged [projections]
Questions about the conversions of a 3D model to a 2D model.
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When fitting 3d cuboids into a box, how to find the order of drawing (in a 2D projection) so that the cuboids don't appear to overlap?
I am working on a 3D packing algorithm (MIT-licensed). The box and the cuboids it contains are displayed as a 2D projection. The order of drawing the cuboids (now represented as polygons) is important:...
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$P^2$ vs projection plane
I want to explain what I understood of definition of the two things.
Projection plane:
The general processing steps for modeling and converting a world coordinate description of a scene to
device ...
user17337
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1
answer
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Computing perspective directly
Assume the screen is axis aligned with origin at 0 and there is absolutely no view transformation.
in other words we will simply try to project the model onto the screen plane following perspective. ...
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Parallel projection is special case of perspective projection
I synchronized with @David k's first and second answer regarding perspective and parallel projection. From the first question I understand that the image on the screen is typically described in ...
user17337
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How is orthographic projection used in computer graphics technically classified as a projection?
I'm wondering why the orthographic projection we use in computer graphics is called a projection, if all it does is just scale and translate a mesh?
According to wiki orthographic projection is ...
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How to translate the center of an equirectangular projection?
I'm trying to perfectly align two or more equirectangular photos of the same place taken from slightly different positions.
Using an example provided by openMVG I managed to get the relative position ...
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1
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Getting from the default view volume to an image on the screen
I don't completely understand the last part of the MVP matrix (projection).
In orthographic projection we simply scale the view volume into the default view volume (+-1 on all axis).
In perspective ...
2
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1
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3D homogenous coordinates versus 4D homogenous coordinates
We know that any 2D point $(x, y) $which represents as 3D homogeneous coordinates is of the form $(x, y, 1)$ which is the points of projective plane $P^2.$
If I use the same concepts for 3D points $(...
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Y axis inversion in 3D rasterization
What is the correct way to invert the y axis during the 3D projection?
I see a lot a people doing:
...
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Intrinsic Matrix vs Perspective projection matrix
I was going through the camera matrix explained in the wikipedia article and understand how the matrix K \begin{bmatrix}f_x&s&x_0\\0&f_y&y_0\\0&0&1\end{bmatrix} is built. The ...
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What exactly is the orthographic projection used by Matlab
I would like to imitate the orthographic projection that Matlab uses by default:
Matlab View Projections
and
Matlab camproj
It seems similar to the "Trimetric" projection described here:
...
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Projective texturing from many images
Problem: I'm trying to dynamically texture a mesh of the real world generated by the Hololens over time using photos also captured from the Hololens, perhaps one photo per second. Each of the photos ...
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A way to save 360° panorama video
What is the best way to save video from faces of a cube? The render can produce 6 squares (90°x90°) of 1024x1024 resolution. Faces oriented along axies and only position is changed continuously. I ...
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Finding Camera projection matrix from known input and output
Lets say I have a rectangle with known coordinates in 3D scene, and I'm projecting it using pin point camera to the plane (screen).
You can imagine it deforms on the screen per camera transformation ...
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Finding a texture pixel (X,Y) on a Sphere
I'm using three.js combined with face recognition, I want to rotate a sphere that displays my input video according to the detected eye location,
the face recognition gives me a X,Y on the texture ...
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